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Does an orbital have its own energy, separate from the electron? If so, is it possible for an electron to have a different energy than the orbital it occupies?

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    $\begingroup$ Nope, energy is not stored in the energy levels themselves but the states which occupy them. The different orbitals and energy levels are just possible states that the electron can be in, some high energy and some low energy. therefore, the idea of an electron and orbital are not separable when talking about atoms and molecules. $\endgroup$ – Cody Aldaz Apr 24 at 19:30
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    $\begingroup$ Does your passport have any money or property of its own, separate from you? $\endgroup$ – Ivan Neretin Apr 24 at 20:28
  • $\begingroup$ Very interesting question. It doensn't make sense to separate the energy, it would be like dismissing a fine because your car couldn't be above the speed limit, just its velocity. But the closest to that, I belive, would be treat the particle and its wavefunction as separate physical entities. That approach was tried by De Broglie and David Bohm early in quantum theory, to solve the duality problem. See pilot-wave theory, and this very nice macroscopic analogue discovered in 2010. $\endgroup$ – ksousa Apr 29 at 23:53
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An orbital of current quantum models of atoms and molecules has 3 major interpretations:

orbital(1) as a wave function, being a solution of the quantum wave equation describing behaviour of electrons around an atomic kernels. Functions do not have energy, even if they describe it.

orbital(2) is the 3D region describing probability of occurance of an electron, related to orbital(1) . Space regions do not have energy either. (Not exactly true, considering radiation energy and quantum vacuum energy, but nothing comparable to the electron energy at usual conditions.)

orbital(3) is a quantum state of an electron, described by orbital (1) and orbital (2), consisting of set of discrete values of physical quantities as functions of quantum numbers, including energy. In the case this quantum state is not occupied, the orbital energy means "an electron would have this energy".


orbital (4) from the obsolete Bohr model means a path of an electron, which is a crude approximation of the quantum model of an atom.


Last, but not least: Orbitals are not physical things, they are part of the quantum theoretical model of atoms and molecules. Within the given quantum model, an electron cannot have different energy than energy of it's quantum state.

As models of multielectron cases are imperfect, real electron energy usually more or less differ from its energy predicted for the given quantum state.

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  • $\begingroup$ I'll add a fourth // orbital (4) - path of an electron in the Bohr model which is a crude approximation of the quantum model of an atom. $\endgroup$ – MaxW Apr 25 at 15:30
  • $\begingroup$ Hmm, I am not sure, it is not interpretation of post Bohr quantum model orbitals. $\endgroup$ – Poutnik Apr 25 at 15:34
  • $\begingroup$ Sorry, that was the point that I was trying to make. The Bohr model isn't the best model but it is a useful step into understanding atoms. It takes considerable math skills to understand/appreciate the quantum model. $\endgroup$ – MaxW Apr 25 at 15:39
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    $\begingroup$ Sure. I have added it. $\endgroup$ – Poutnik Apr 25 at 15:40
  • $\begingroup$ Thank you for your responses. If orbitals don't really exist by themselves as separate entities, why do we talk about them that way? Example: when reading about the hydrogen atom, my textbook comments that 2s and 2p are actually degenerate for hydrogen... but those are unoccupied and hence shouldn't exist. $\endgroup$ – Kameron Shrum Apr 30 at 12:57

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